As is known in the art, it is desirable to know when stray radiation is present. Conventional radiation monitors, e.g., beam loss monitors (BLMs), are very expensive, are relatively slow in detecting radiation, require high voltage power, and have high bias voltages, e.g., greater than 1000V.
One type of known detector requires a conventional detector material coupled to photomultipliers (PMTs). The response time of PMT-based BLMs is in the order of 0.1 μs to 1 μs. In addition, PTMs are relatively fragile and prone to gain shifts with changes in temperature.
Another known detector is referred to as a scintillation counter that measures ionizing radiation. The scintillator includes a transparent crystal, such as phosphor, a plastic, typically containing anthracene, or an organic liquid that fluoresces when struck by ionizing radiation. A photomultiplier tube (PMT) attached to an amplifier measures the light from the crystal. However, such devices may require the use of toxic materials and are relatively slow.
In addition, known BLMs are prone to false alarms. For example, some locations have relatively high levels of natural radiation. These radiation levels can trigger the BLM resulting in false alarms. As will be readily appreciated, false alarms are undesirable since complex and costly equipment must be ungracefully shut down, which can have significant adverse consequences.